Aussie

Good to hear that you got the maiden in and most likely found out how well this thing floats and how powerful the elevators are even at such a small throw...

Here is what I do for all my pitts mufflers, both gas and glow. Use the spring washers you are talking abot but also use some of the red Permatex high temp gasket maker that you use for cars. Open the tube, push each bolt into the tube until the threads are covered, then bolt the muffler on. Before you reinstall the cowl, run the engine for a few minutes to warm it. Now retighten the bolts and you should be good to go